Truck bed liners thermoformed from plastics such as high density polyethylene (HDPE) are commonly used to protect the surface of a truck bed from being scratched and deformed. Typical truck bed liners are thermoformed to have a ribbed pattern. Each longitudinal rib extends vertically above the base level of the truck bed liner to a height chosen to provide an optimum amount of cushion and protection to the metal truck bed while maintaining a maximum useful cargo height, as defined by the floor of the truck is bed liner and the top of the bed side walls. Such truck bed liners contain alternating longitudinal sections of ribbed and flat surfaces. The flat surfaces of the bed liner make contact with the metal truck bed. Each ribbed surface creates a void between the bed liner and the bed. These voids are beneficial in providing extra protection to the metal bed against deformations by sharp objects, etc.
Although such plastic truck bed liners are beneficial in protecting the metal truck bed, the surface of plastic truck bed liners provide substantially less friction than does a metal truck bed. This reduced surface friction is deleterious for the purpose of transporting cargo on the truck bed. Commonly transported cargo objects such as tool boxes, gasoline cans, tackle boxes, and such, tend to slide across, and topple over on a truck bed covered with a plastic liner, much more than with an unlined metal truck bed during transport.
U.S. Pat. No. 5,648,031 discloses a liquid polymer especially developed for increasing the friction of HDPE or other thermoplastic material. The liquid polymer is used by spraying or otherwise applying the polymer to the surface of the truck bed liner. However, the effectiveness of such liquid topical additives tends to be short-lived due to wear.
U.S. Pat. No. 5,549,428 discloses another approach for stabilizing cargo during transport on a truck bed liner. That patent discloses a set of anti-skid devices that sit atop of the ribbed bed liner and tightly cup around a portion of one of the liner ribs in order to remain stationary. The top side of the anti-skid devices is elevated above the bed liner ribs to provide a raised barrier. When a multiple number of such devices is placed strategically around a cargo object, the object is prohibited from sliding during transport by engaging with at least one of the anti-skid devices. The undesirable aspects of such an anti-skid device is that truck bed liners are manufactured with a broad variety of rib widths, depending on the manufacturer. Therefore, a set of anti-skid devices would fit only a limited number of truck bed liners. The raised anti-skid devices would tend to prohibit the sliding of heavy objects across the devices and positioning objects atop of the devices. Therefore, one would occasionally need to remove the anti-skid devices from the bed.
U.S. Pat. No. 5,597,193 discloses an interlocking truck bed liner having a plurality of perpendicularly intersecting, rectangular-shaped horizontal grooves and a plurality of interlocking panels which fit within the grooves to create vertically extending walls useful for boxing in cargo objects. Such an assembly would be very cumbersome since the vertical wall panels would have to be removed from the bed liner in order to use the floor area blocked off by the interlocking panels for jobs such as hauling truck bed loads of lumber or other large objects requiring use of the entire truck bed.
In light of the above, it would be desirable to provide a permanent means of stabilizing a cargo object atop of a section of a thermoplastic truck bed liner without requiring removal of the stabilizing means in instances where that section of bed liner is needed for other purposes such as hauling large loads requiring essentially all of the bed surface.